Item 63 The data set shows the numbers of hours students study the week before a test. Find and interpret the mean absolute deviation of the data. Write your answer as a decimal. 1, 1, 1, 3, 4, 5, 6, 7, 8, 10 The data values differ from the mean by an average of hours.

the first one is x^2+2x+2

the second one is x^2+4

the last one is x^2-4x+8

0.50 , 0.75

step-by-step explanation:

let x and 400 - x be the two numbers.  

==> 0.80x + 0.85(400 - x) = 400 - 68 from the statement of the problem.  

< ==> 0.80x + 0.85(400 - x) = 400 - 68  

==> 340 - 0.05x = 332  

< ==> -0.05x = -8 ==> x = 160, the first number ==> 400 - x = 240, the second number.